With the release of Reaver, Harbinger now has a lot more utility outside of Apex decks. Any deck running Aesop's Pawnshop and Reaver should consider splashing another 3 influence to slot 3 Harbingers.

Installing 1 Harbinger for a click gives the runner 6 credits and 2 card draws over the next 2 turns once the engine is set up. Being a program, Harbinger also fires Technical Writer for an additional 1-3 credits to be collected when required. 1 click for 6-9 credits and 2 cards is pretty nuts, and Hayley goes one step further by allowing you to install 2 Harbingers in 1 click. That's 12-18 credits and 4 cards being drawn for a click (over 4 turns though). Using a Clone Chip to bring Harbinger back (making sure to fire the Clone Chip on the corps turn for that extra draw from Reaver) just makes sure Aesop is never out of stock.

On top of this, whilst Harbinger is waiting to be sold by Aesop, he acts as a great target if the corp forces the runner to trash an installed card (like Power shutdown).

7 influence for Reaver for 3 Harbingers out of Shaper is a steep ask, and you if you have to import Aesops too the total influence hits 13 which is something only Sunny would seriously consider.

But outside of Apex, it can serve a different purpose - when comboed with Aesop's Pawnshop, it's worth 3. Twice. Cards that you can play for 0, and that give you equivalent returns to Lucky Find are pretty rare. (Without being a double, and for half the influence, to boot!) You can bump it up even further with Wasteland.

The idea behind Harbinger is that it can be trashed twice by cards that need installed card trashing to fuel their abilities, like Endless Hunger: the first time you turn it facedown, the second time it goes to your heap.

You also want to make sure you have a Harbinger out before you run with Endless Hunger on the board, if you're anticipating an X=0 Power Shutdown.

Does Harbinger work with Faust? This is the same sort of thing that Tri-maf Contact deals with, and in that case, if you trash the Tri-maf from your hand then you don't take the damage since it isn't in play beforehand. Precedent says that the same thing would happen here: Harbinger gets trashed from grip and goes straight to heap.
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ReploidArmada10 Nov 2015

Harbinger does NOT work with Faust. Unless the card effect necessitates it (like I've Had Worse) cards in players' hands are not active.
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tiedyedvortex10 Nov 2015

Is it still a 0 cost card for power shutdown when its face down?
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sodapopinski20 Jun 2016

No, it would no longer be eligible as a target for Power Shutdown since it is neither a program nor hardware when facedown. A flipped Harbinger will not protect your Endless Hunger.
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Nidhogg29 Jun 2016